PHOENIX (AP) -- Opponents of a provision in Arizona's "Clean Elections" campaign law urged a federal judge on Thursday to bar the state from giving out matching funds when privately funded candidates outspend their publicly funded opponents.

The critics contend matching funds are unconstitutional, and suggested instead that dozens of potentially affected candidates could be allowed to seek private contributions.

That would be a big change for publicly funded candidates, whose only fundraising has consisted of collecting $5 qualifying contributions from voters.

Supporters of public campaign funding said it would unfair and impracticable to change the system this close to the Nov. 4 general election.

U.S. District Roslyn Silver said in a preliminary ruling issued in late August that matching funds are unconstitutional, but she heard arguments Thursday on whether to stop them while the case moves toward a trial and a likely appeal higher in the federal court system.

Candidates participating in the state's "Clean Elections" campaign funding system receive base funding allotments for campaigns as well as additional "matching fund" dollars if privately funded opponents raise more cash than they do or if independent groups begin spending.

Of the 107 candidates for Corporation Commission or legislative seats receiving public funding for the general election, 63 could be at least theoretically eligible to receive matching funds. Of those, 22 have already achieved some matching funds as of Thursday, including eight who have already received the maximum $38,764 for legislative candidates.

A tally sheet released by the state agency that administers the program, the Citizens Clean Elections Commission, said participating candidates received a total of $2.4 million of base funding and $454,581 in matching funds as of Thursday.

Significant amounts of matching funds are triggered by private fundraising and spending in the last month of the campaign, said Todd Lang, the commission's executive director. "There's always last-minute attack ads."

The case is based on two lawsuits filed on behalf of Republican legislative candidates and others. Their lawyers argue that matching funds infringe on their First Amendment free speech rights by having a chilling effect on private fundraising because it cold trigger matching funds.

Bill Maurer, an Institute for Justice lawyer representing some of the plaintiffs, said any perceived hardship caused by a ban on matching funds could be reduced if the state invokes an emergency provision in the Clean Elections law that permits candidates to accept private contributions if the state can't provide public money.

But the underlying issue is that publicly funded candidates aren't entitled to money provided unconstitutionally, Maurer said. "Quite frankly they had no expectation of this money."

A lawyer for an advocacy group that supports public campaign funding said it would be a hardship for participating candidates to cut off matching funds.

It's "simply fantasy" to think that publicly funded candidates could gear up for private fundraising in the last week of the campaign for a late attack by an independent expenditure group, said Bradley S. Phillips, a lawyer representing the Clean Elections Institute.

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On the Net:

Citizens Clean Elections Commission: http://www.ccec.state.az.us/

Clean Elections Institute: http://www.azclean.org/

Institute for Justice: http://www.ij.org/index.shtml

Goldwater Institute: http://www.goldwaterinstitute.org/

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